Molten metal charging means for a furnace



- Oct. 14, 1969 J. s. CAMPBELL 3,472,942

MOLTEN METAL CHARGING MEANS FOR A FURNACE Original Filed May 25, 1964 2 Shgets-Sheet 1 INVENTOR. JAMES SAMUEL CH WPBELL ATTORNEY Oct'. 14, 1969 J. s. CAMPBELL 3,472,942

MOL'IEN METAL CHARGING MEANS FOR A FURNACE Original Filed May 25, 1964 2 Shets-Sheet 2 & l I] 2 t :2 FIG -3- 2 q a Q i E 3 9 Q Q 390 5 b .7

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INVENTOR JAMES SAMUEL CAMPBELL ATTORNEY United States Patent 3,472,942 MOLTEN METAL CHARGING MEANS FOR AFURNACE James Samuel Campbell, 74 Sleepy Hollow Lane, Orinda, Calif. 94563 Original application May 25, 1964, Ser. No. 369,669, new Patent No. 3,380,511. Divided and this application Feb. 8, 1968, Ser. No. 703,980

Int. Cl. H0511 /12 U.S. Cl. 13--33 5 Claims ABSTRACT OF THE DISCLOSURE Ingots are melted into a funnel having a flow connection to the interior of a furnace. The ingots are melted by a winding in a receptacle above the funnel such that the charge flows through the funnel and into the furnace in a molten state.

This application is a division of my application for System and Method of Casting filed May 25, 1964, SN. 369,669 now Patent Number 3,380,511.

My invention relates to furnaces adapted for dispsening of molten metal, and more particularly means for charging such furnaces.

Among objects of my invention are:

(1) To provide novel and improved charging means for a furnace (2) To provide novel and improved charging means for supply metal in molten state, to a furnace (3) To provide novel and improved charging means for converting metal from solid state to the molten state and automatically feeding same in its molten state to a furnace (4) To provide novel and improved charging means for converting metal from solid state to the molten state and automatically feeding the same in its molten state to a furnace as the conversion to the molten state occurs.

Additional objects of my invention will be brought out in the following description of the same taken in conjunction with the accompanying drawings wherein:

FIGURE 1 is a view in section through a furnace system to which the invention is applicable;

FIGURE 2 is a view in section depicting a detail in the apparatus of FIGURE 1; and

FIGURES 3 and 4 are views in section, through furnace charging means adapted for supplying molten metal to the furnace apparatus of FIGURE 1 in accordance with the present invention.

Referring to the drawings for details of my invention in its preferred form, the same involves a system which basically comprises a furnace assembly 1 having a pouring tube assembly 3 associated therewith for delivering molten metal from the furnace assembly to a mold 5 Supported on an elevation adjustable mold platform 7, with means for maintaining all exposed molten metal in the system protected from adverse influences.

The heart of the furnace assembly lies in a furnace refractory pot 9 formed of a suitable material capable of handling a specific molten metal without contamination of such metal. For aluminum, the pot may be of cast iron 11 coated over its interior surface with any refractory material 13 capable of protecting the molten aluminum from contamination by the iron. One such material is known to the trade as Kirkote. If the pot be made of silicon carbide, then no coating would be required.

The furnace pot is preferably formed to provide a rear Wall 17 of the greater depth than the opposing or front wall 19, with a bottom 21 joining the front and rear walls, thereby causing the bottom to slope downwardly toward the rear wall with the pot in its normal position 3,472,942 Patented Oct. 14, 1969 ice for filling. A pouring spout 23 terminating in a flange 24, extends from the front wall, substantially tangential to the bottom 21.

The furnace pot is supported on legs 25, or equivalent base, in an insulated cylindrical shell 29, including a cover or lid 30 having a flue 31 installed therein. Adjacent the bottom of the shell is a burner flame passageway such as to direct flame from an installed gas burner 33, against the lower regions of the furnace pot, from where the burning gas will be caused to rise about the pot to ultimately exhaust itself through the flue.

To more effectively control the flow of the heating gases along the furnace pot, as such gases rise from the burner to the flue, a spiral guide baffle 37 encircles the furnace pot, spanning the space between it and the surrounding shell. Such spiral guide baffle may well be cast integral with the pot.

This spiral baffle, in conjunction with the pot and the shell, defines a spiral flow path for the heating gases generated by the burner, whererby such gases must follow in such spiral path around the pot to bring about substantially uniform and efficient applications of heat thereto.

The pouring tube assembly 3, includes a pouring tube 41, preferably of stainless steel or equivalent material, and carries a nozzle assembly 45, coupled to the free end of the pouring tube by a hollow T-coupling 47.

The pouring tube with a flange 49 at each end, is connected at one end to the flange 24 of the furnace pouring spout 23.

Because stainless steel may be attacked by molten aluminum, then if aluminum is to be handled thereby, the pouring tube, prior to assembling the same into the system, is lined with any suitable protective refractory material 57, preferably material available under the trademark Fiberfrax, either as a cement or in the form of a paper.

Information as to this material and method of producing the same may be found in the patents to Mc- Mullen 2,557,834 of June 19, 1951; McMullen 2,266,821 of Aug. 17, 1954; Meaters 2,704,603 of Mar. 22, 1955; McMullen 2,710,261 of June 7, 1955', Nicholson 2,731,359 of Jan. 17, 1956; and Auer 2,274,336 of Apr. 1956.

If the furnace spout 23 be of a material which might conceivably contaminate the molten metal being handled, it will be treated in the manner of the pouring tube 41, to provide it with a neutral refractory lining.

In assembling the pouring tube, as thus prepared, to the furnace spout, a gasket 58 is inserted between opposing flanges and the pouring tube is then bolted to the spout.

The T-coupling 47, involving a stem 60 and cross arm 61, is preferably flanged at its stem end, and at each end of its cross arm, and after being treated in the manner of the pouring tube 41, to provide it with a protective refractory lining throughout its internal surfaces and exposed coupling surfaces of its flanges, it is affixed at its stem end, with an intervening gasket, to the free end flange of the pouring tube, with the cross arm in a generally vertical direction.

The nozzle assembly 45 comprises a nozzle 63 which, like the pouring tube 41 and T-coupling 47, is formed preferably of stainless steel, with an inner wall 65 concentric With a shorter outer wall 67, both walls being joined along their bottom edges as by welding, to form the tip of the nozzle. The nozzle 63 is tapered in order to maintain a full flow of metal during pouring.

The inner wall of the nozzle terminates at its upper end in a flange 69 for coupling to the proximate flange of the cross arm of the T-coupling.

The inner surface of such inner wall 65 and the associated flange 69 are treated preferably in a manner similar to the pouring tube 41, prior to coupling the nozzle to the T-coupling, to provide protective refractory lining 71 which is extended out through the discharge tip of the nozzle and then carried up the outer surface of the outer wall 67 for a short distance, of the order of two or three inches, so that the tip of said nozzle will be completely protected by refractory material which is not attacked by molten aluminum or other molten metals.

Following the coupling of the nozzle assembly to the pouring tube by the T-coupling, the pouring tube, T-coupling and upper portion of the nozzle assembly are covered with a thick layer of heat insulation 75 and then encased in an enclosure 77 of sheet metal.

In the use of the furnace and pouring tube assemblies as described above, three main positions are contemplated, namely, a melt position, a pour position, and an intermediate hold position approaching the pour position, or in other words a position where the molten metal level in the pouring tube assembly approaches the highest point in the pouring tube and close to flowing over into the nozzle.

A pivot 85 on each side of the furnace, permits of suspending the furnace for tilting.

Charging of the furnace may be accomplished by introducing ingots into the pot, to be melted therein, or other conventional procedures may be utilized.

Under certain conditions, one may, however, prefer to supply metal to the furnace in molten form rather than in its solid state, and utilizing apparatus adapted for such use.

One such apparatus may take the form of a filling tube 383, comprising a hollow stem 384 terminating at its upper end in a funnel 385, which is closed with a removable cap 386. The filling tube is supported at its funnel end, which funnel, externally, has a hemi-spherical (or semi-cylindrical) bottom adapted to rest in a complementary hole 387 through a supporting member 388 above the furnace, with the lower end of the filling tube passing frictionally through a combination swivel and sliding joint 389.

Such joint is preferably formed from a block 390 having a longitudinal passageway therethrough to rotatably receive a cylindrical swivel 391, the swivel being provided with a diametrical opening therethrough to slidably receive the hollow stem 384.

To permit tilting of the furnace while allowing the filling tube 383 to remain fixedly installed, the block 390 has a linear recess 392 in both its top and bottom sides, in the plane of swing of the stem 384 relative to the block and of a width exceeding the diameter of the stem. Inasmuch as the furnace tilts to one side of the vertical only, these linear recesses may be ofiset with respect to each other and extending at one end but slightly beyond the stem.

Such filling tube will be employed when the metal is reduced to molten condition in another furnace, with the furnace of the present invention being used as a pouring and cleansing furnace, or with slight change, may be utilized with an ingot heater, preferably one utilizing the principle of induction heating.

In such latter type of feed device, the filling tube employed, differs slightly from that of the preceding filling tube, in the shape of its funnel 393, which, externally, is

spherical or cylindrical, to provide a swivel fit with a socket recess in the bottom of an induction heating receptacle 394. This receptacle is formed with an inclined chamber 395 opening at its discharge end, to the funnel, and adapted at its intake end, to receive ingots fed thereto by gravity, through a feeding tube 396.

Embedded in the walls of the receptacle 394, is a winding 397 to which may be supplied alternating current, such winding being preferably increasingly crowded toward the bottom of the receptacle, to increasingly generate more and more heat in the ingots as they move downwardly in the chamber, and as the ingots melt, the resulting molten metal will flow into the furnace pot below.

It will be apparent from the foregoing that the invention as described fulfills all the objects thereof, and while I have illustrated and described the same in its preferred form, the invention is subject to alteration and modification Without departing from the underlying principles involved, and I accordingly do not desire to be limited in my protection to the specific details illustrated and described, except as may be necessitated by the appended claims.

I claim:

1. Furnace apparatus adapted for use in a system for casting of molten material comprising a furnace assembly including a furnace receptacle and means providing a cover therefor,

and means for charging said furnace receptacle with material in molten condition, said last means including,

a tube passing through an opening into said receptacle,

a funnel at the upper end of said tube,

and means associated with said funnel for converting material from solid state to a molten condition to supply such material to said furnace.

2. Furnace apparatus in accordance with claim 1, characterized by said means for converting material including means in flow communication with said funnel for holding material in its solid state, and means for heating said material to a temperature high enough to assure melting thereof.

3. Furnace apparatus in accordance with claim 2, characterized by said heating means including a heating winding.

4. Furnace apparatus in accordance with claim 3, characterized by said heating winding being more concentrated in the flow direction of said material.

5. Furnace apparatus in accordance with claim 3, characterized by said winding being an induction heating winding.

References Cited UNITED STATES PATENTS 1,874,417 8/1932 Baily 13-33 3,163,520 12/1964 Collin et a1. 1333 X BERNARD A. GILHEANY, Primary Examiner R. N. ENVALL, 111., Assistant Examiner US. Cl. X.R. 266-27 

